| A. T. Site Services Ltd. | Coventry | 2005 |
| A. Teale Roofing Ltd. | Manchester | 2005 |
| A. Thames & Cook Limited | Bramhall | 2003 |
| A. Thompson Consulting Limited | Northallerton | 2003 |
| A. Thompson Decorators Limited | Leicester | 2025 |
| A. Thorpe Construction Limited | Clacton-On-Sea | 2007 |
| A. Tottie Limited | Armley | 2015 |
| A. Townsend Build Limited | Southam | 2023 |
| A. Tyrer & Sons (Roofing) Limited | Cheshire | 1990 |
| A. V. Construction West Midlands Limited | Chorley | 2017 |
| A. Venn (Surrey) Builders Limited | Dorking | 1977 |
| A. Venning Limited | Chorley | 1982 |
| A. Vincent Groundworks Limited | Cosham | 1997 |
| A. Vines Ltd | Wiltshire | 2003 |
| A. W. Cuff Ltd | Dorset | 2002 |
| A. W. Electrical Northwest Ltd | Liverpool | 2018 |
| A. W. P. Potter & SON (Engineering Services) Limited | Bewdley | 2003 |
| A. W. Plastering (Essex) Limited | Leigh On Sea | 2015 |
| A. W. Sturmey Limited | Wolverhampton | 2013 |
| A. W. Walker (Europe) Limited | | 2005 |
| A. Wainwright Construction Ltd | Nottingham | 2023 |
| A. Wall Brickwork Limited | Chester | 2003 |
| A. Wall Building Contractor Limited | Wrexham | 2003 |
| A. Ward & SON Limited | Nottingham | 1995 |
| A. Ware Electrical Services Limited | Hull | 2003 |
| A. Watt. Electrical Ltd. | Colchester | 2009 |
| A. Weatherhead Drilling Services Limited | Aylesbury | 2002 |
| A. Welbourne Electrical Limited | Nottingham | 1995 |
| A. Westwood Roofing Ltd | Wednesbury | 2023 |
| A. Whitham Decorating Contractors Limited | Radlett | 2005 |
| A. Willingham Limited | Kent | 2003 |
| A. Wilson & Sons (Islington) Limited | Ware | 1980 |
| A. Withey Paving Limited | Southampton | 2013 |
| A. Witt Builders Limited | Chippenham | 2003 |
| A. Wright Contractors Limited | Ormskirk | 1995 |
| A. Wring Group (Demolition Co.) Limited | Bristol | 1979 |
| A.& B. Brown Building Services Limited | Glasgow | 2009 |
| A.& C. Electric, Limited | Belfast | 1952 |
| A.& E.Baines Limited | Harrogate | 1951 |
| A.& E.Elkins Limited | London | 1965 |
| A.1. Kitchens and Bathrooms Limited | Nottinghamshire | 1991 |
| A.1.S. Plumbing & Heating Services Ltd | Derby | 2013 |
| A.A Electrical Leicester Ltd | Leicester | 2022 |
| A.A Home Installation Limited | Weston-Super-Mare | 2026 |
| A.A Pro Platforms Ltd | London | 2025 |
| A.A Property Maintenance Services Ltd | London | 2025 |
| A.A Utilities & Groundworks Ltd | Pontefract | 2024 |
| A.A Wait Painters Ltd | Leigh-On-Sea | 2025 |
| A.A. Arnold (Electrical Contractors) Limited | | 1987 |
| A.A. Clare & SON Limited | Caterham | 2008 |
| A.A. Consultancy Limited | Ascot | 2012 |
| A.A. Direct Refurb Limited | Cannock | 2008 |
| A.A. Dunlop Limited | Belfast | 2007 |
| A.A. Dunlop NO. 2 Ltd | Belfast | 2025 |
| A.A. Eades and SON Limited | Newbury | 2010 |
| A.A. Electrical Installations Services Limited | Middlesex | 2003 |
| A.A. Field Mechanical Services Limited | London | 2005 |
| A.A. Fisher (Developments) Limited | Wiggenhall Road Watford | 2003 |
| A.A. Floor Services Limited | Essex | 1992 |
| A.A. Frances and Sons Limited | Redditch | 1985 |
| A.A. Harrison & Sons Ltd | Godalming | 2003 |
| A.A. Jupe Developments Limited | Christchurch | 1987 |
| A.A. Taylor General Builders Limited | Cambridge | 2002 |
| A.A. Young Ltd. | Edinburgh | 1992 |
| A.A.& A.S. Limited | Reigate | 1997 |
| A.A.A Constraction Ltd | Rushden | 2022 |
| A.A.A. Bathroom Supplies & Installations Ltd | Leigh-On-Sea | 2011 |
| A.A.A.S Build Limited | London | 2017 |
| A.A.C. (Southern) Ltd | Littlehampton | 2000 |
| A.A.C. Waterproofing Limited | Bolton | 1989 |
| A.A.D Joinery Ltd | Glasgow | 2023 |
| A.A.K Electrical Installations Ltd | Leeds | 2010 |
| A.A.L. Construction (Scotland) Ltd | Buckie | 2016 |
| A.A.M Transport Ltd | Plymouth | 2026 |
| A.A.M. Plumbing & Heating Ltd | East Grinstead | 2021 |
| A.A.N. Contracting Ltd | Grantham | 2023 |
| A.A.S. Contractors Ltd | Gateshead | 2021 |
| A.A.S.K Heating Services Ltd | Glasgow | 2018 |
| A.A.Scottdevelopments Limited | Shildon | 2025 |
| A.A.Solution X1 Ltd | Glasgow | 2022 |
| A.A.T. Const. Ltd | Glasgow | 2025 |
| A.Armstrong Wind Services Ltd | Newcastle Upon Tyne | 2023 |
| A.B Construction (Glos) Limited | Gloucester | 2008 |
| A.B Electrical Leeds Ltd | Leeds | 2022 |
| A.B Installations Ltd | Kettering | 2018 |
| A.B Mechanical & Heating Services Limited | Ballynahinch | 2025 |
| A.B Paint and Repair Limited | Sawbridgeworth | 2026 |
| A.B Payne Ltd | Newport | 2019 |
| A.B Plastering Services Ltd | Nottingham | 2026 |
| A.B Plumbing Solutions Ltd | London | 2025 |
| A.B Postlethwaite & SON Ltd | Bowness-On-Windermere | 2025 |
| A.B. (NE) Limited | Ryton | 2013 |
| A.B. 2000 Ltd. | South Lanarkshire | 1995 |
| A.B. Camp Contractors Limited | Derby | 1986 |
| A.B. Commercial Surveyors Ltd | London | 2014 |
| A.B. Construction Building & Development Limited | London | 1998 |
| A.B. Developments (East Anglia) Ltd | Wisbech | 2024 |
| A.B. Electrical (Ipswich) Limited | Ipswich | 2011 |
| A.B. Polzeath Limited | London | 2012 |
| A.B. ST Ives Limited | London | 2011 |